Electromagnet and magnetic switch mounting



Nov. 4, 1958 H. E. scHLElcHER 2,859,302

ELECTROMAGNET AND MAGNETIC SWITCH MOUNTING Filed June 14, 195e 'nitcd States Patent l ELECTROMAGNET AND MAGNETIC SWITCH MOUNTING Harold E. Schleicher, West Hartford, Conn., assignor to The Arrow-Hart & Hegernan Electric Company, Hartford, Conn., a corporation of Connecticut Application June 14, 1956, Serial No. 591,414 9 Claims. (Cl. 200-104) This invention relates to electromagnetic switches and more particularly to means for mounting the switch and the electromagnet structures.

It is sometimes necessary to repair, replace or inspect the electromagnet coil, field piece or armature, or all three. It is desirable to be able to do that with minimum .amount of disturbance of the wiring and without the need to remove or touch the fixed and movable contacts.

Therefore, it is an object of this invention to mount :the electromagnet structure in such a way that it can be :swung away from the switch or mounting plate without .disturbing the tlxed and movable contact assembly and wiring and without abnormally moving or disturbing the :movable contact carriage.

Another object of the invention is to provide a readily removable electromagnet structure having the aforesaid characteristics which will, nevertheless, be rugged and reliable in service, can be economically manufactured and sassembled, and will operate with better efficiency and .accuracy and without sacrifice of power and eiciency.

It is sometimes desirable to be able to mount the electromagnetic switch as a unit on a prepared mounting or base and terminal structure which may include amounting plate and terminal block.

Thus, another object of the invention is to provide an electromagnet magnetic switch unit which is guided for :mounting with a straight line motion and which can be .secured by merely tightening the guide screws.

Another object of the invention is to provide an electromagnetic switch structure which may be mounted upon Aa base and a terminal mounting arrangement which can .also be used as a complete electromagnetic switch unit '.when the aforesaid mounting is not needed or not wanted.

Other objects of the invention will become apparent as f it is described in connection with the accompanying drawzing.

in the drawing:

Fig. l is a plan View of an electromagnetic switch structure and mounting embodying the invention.

Fig. 2 is a side elevation view, partly in section, taken along line 2 2 of Fig. l of the mounting plate and terminal structure.

Fig. 3 is a side elevation view of an electromagnetic switch structure which can be mounted upon the plate and terminal structure illustrated in Fig. 2, the switch of Fig. 3 being separated from the structure of Fig. 2.

Fig. 4 is an end elevation view of the structure illustrated in Fig. l.

Referring to the drawing, a block of molded insulation 12 is mounted on a metal back plate 10 which at one end may be turned up and around an extending foot 14 of the block 12.

The block may be of L-shape-with the foot 14 being against the back plate 10. One face of a forwardly extending portion of the block 12 is recessed on one side for a plurality of identical sets ortpairs of wire terminals consisting of an upper and a lower terminal 16 and 18, three sets being shown. The terminals are stamped in 2,859,302 Patented Nov. 4, 1958 strip form from sheet metal into L-shape and are secured to the block by bolts or rivets 15 with one leg of each terminal perpendicular to the backplate. One leg of the terminals of each set is in alignment. The other legs of the terminals may extend away from the block substantially and have screws provided thereon for attaching conductor Wires. Recesses behind the terminals 16 and 18 may be provided to receive receptacle contact members 17 and 19 riveted or otherwise secured to the aligned legs of the terminals. Such receptacle contacts may be stamped from thin sheet metal in strip form and bent into U-shape with their ends reversely bent toward each other to provide flexible jaws between which will be received prong contacts as hereinafter described.

Access to the jaws is provided by slots formed in the opposite base of the block from the wire terminals 16 and 18 in register with the contact jaws. The insulating block supporting the terminals may be bolted or otherwise secured to the backplate. The backplate, together with the block and terminals carried thereby, thus forms a mounting and terminal structure which, as will presently appear, may receive an electromagnetic switch unit which will now be described.

A complete electromagnetic switch unit as illustrated in Fig. 3 has extending prong contacts 31 and 33 which may be plugged into and engage with the wire terminal jaws 17 and 19 as the unit is slid along the backplate 10 toward the terminal block 12.

The parts of the electromagnetic switch unit are mounted upon a sheet metal base plate 20 which has a pair of similar key-hole slots 22 and 24 in the corners of one end to receive a pair of guide and securing studs in -the form of screws 25 and'27 threaded into tapped holes in the backplate 10 and located in position to allow the headsof the screws to enter the enlarged portion of the key-hole slots as the switch plate is placed on the backplate 10. Then, as the switch plate is slid over the backplate toward the terminal block, the narrow portion of the slots slides along the screw shank and under the screw heads. In this way the switch plate is guided as it slides over the back plate. Tightening of the screws 25, 27 secures the switch plate 20 on the backplate 10. Equivalently studs could be mounted in the switch plate to engage in guide slots in the backplate.

.The fixed contacts 31, 33 of the switch unit can compriseL-shaped sheet metal stampings secured by bolts to upper and lower molded insulation blocks 30 and 32 mounted upon one another and secured to the switch base platev20 by long mounting bolts 19 passing through both and entering tapped holes in the base plate 20. Cooperating abutting surfaces of the blocks 30 and 32 are hollowed out to provide cavities receiving the fixed contacts 31 and 33. The longer leg of each contact extends parallel to the base plate 20. These legs of each pair of contacts are spaced from each other and are in alignment with one another forwardly of the plate 20. These legs thus provide extending prongs which are positioned to be in alignment with the jaw members 17 of the terminals.

As the electromagnetic switch unit is moved along the backplate 10 toward the terminal block, the prongs enter the contact jaw recesses and engage the jaws 17, 19. The motion of the unit is substantially in a straight line because the unit is guided at one end by the prongs entering and being guided by the walls of the jaw slots in the terminal blocks while at the other end the unit is guided by the key-hole slots engaging the guide and securing screws.

Contact buttons 31a and 33a of conventional form are mounted upon the short coplanar legs of the fixed contact members 31 and 33 and face in the same direcsecuredrto the insulating carrier block 44 so thatv all move simultaneously when the carriage is moved.

The structure of the cages 42 and the mounting ofj the contacts dll and the mounting vof the cages upon the insulating block 44 are more fully vdescribed and claimed in my copending application 'Serial No. 591,413, entitled Contact Supporting7 Means for Electromagnetic switches.

The number of bridging contact members will be equal to the number of sets of fixed contacts.

The contact-carrying carriage has a Z-shape at one end with arms 43 and 445 parallel to the backplate and joined to each other by an arm-6 which is perpendicular to the backplate. The contact carrier block 44 which carries the cages and movable contacts is secured to the arm 43 by bolts or otherwise. The carriage arm 45 lies just above the surface of the switch supporting plate 20 and is guided for movement thereover. At the aforesaid end, the carriage is supported 'by a strut 48 having a knife edge at one end which engages the underside of the arm 43 and also engages the backplate 2l), preferably by two short finger extensions or bifurcations at the other end of the strut and entering small slots or apertures punched in the plate 2t) and of sufficient size to allow free pivotal movement of the strutjas the Contact carriage is moved by the electromagnet armature.v The strut thus gives substantially frictionless knife edge support to said end of the carriage. Rectilinear move-k ment of the carriage is also insured by a guide stud 29 mounted in the backplate 21B and extending up through the carriage arm 45 which has a guide slot to receive the stud.

At the opposite end of the carriage from the contact supporting block a pair of parallel arms 47 are bent up from the carriage perpendicular to the backplate and spaced apart. Between these arms 37, a T-shaped laminated armature 52 is mounted upon a pin 53 passing transversely through the head of the T and also through the ends of the parallel arms 17 of the carriage. The leg 51 of the T extends into the solenoid coil 59 which is mounted upon the middle leg 56 of an E-shaped field piece whose upper and lower parallel arms 54, 55 are adapted to attract the head of the armature when the solenoid coil is energized, in well known fashion.

For mounting the eld piece securely but detachably upon the backplate 2t), end plates 57 of generally I -shape are provided having feet 57a lying on the surface of the backplat'e Ztl and secured thereto by screw bolts 57h. The movement of the T-shaped armature is guided by a slot 62 formed parallel to the backplate in the endsl of parallel arms of a U-shaped mounting bracket 60 attached to the back-plate 2t). The arms ofthe lbracket lie outside of the arms 47 of the carriage sothat the carriage and magnet armature can move between the arms of the supporting bracket. i

By the aforesaid construction, it is possible to remove the electromagnet structure by swinging it about the Y.pin 53. This is accomplished without disturbing the movable contact structure or the carriage in their mounting upon the switch plate Ztl. It is only necessary to disconnect any conductor wires which may be connected to the Vsolenoid coil and then to unscrew the bolt 5`7b by which the field piece is attached to the backplate. There is sufficient room for the armature, solenoid coil and field piece to be swung together as a unit about the pin 53 from the full line position shown in Fig..3 to the dotted line position. In that position, the field Vpiece and coil can be separated from the armature and separately inspected or replaced. If desired ornecessary,

the field piece can be moved slightly toward the armature and the supporting `bracket while at the same time the carriage can be moved toward its energized position.

From the foregoing it will be observed that the electromagnetic switch unit, illustrated in Fig. 3 as separated from the terminal mounting structure of Fig. 2, is useful separately as a complete electromagnetic switch structure. -When so used, wire terminal clips having binding screws may be fastened onto the extending prongs 31 of the electromagnetic switch unit. Such clips are shown as applied to the extensions of the terminal 16 in Fig. 1. When it is desired to use the electromagnet switch structure unit in connection with the plug-in terminal mounting of Fig. 2, the wire terminal clips are not used.

The unit may be easily and quickly assembled upon the mounting and terminal structure by laying the switch plate 20 on the'backplate 10 with the heads of the screws 57b extending through the enlarged portions of the key-hole slot 22 and inserting the prongs 31 and 33 in the slots in front of the terminal jaws 17 and 19. Then the switch unit is pushed toward the terminal block to fully engage the prongs 31 and 33 with the jaws 17 and I19. Such movement'is a guided substantially rectilinear movement, as described.

Y armature 'can be swung pivotally away from the backplate.

t Many modifications within the scope of the invention will occur to those skilled in the art. Therefore I do not limit the invention to the specific form and structure described.

What I claim is:

l. A switch-unit mounting comprising a base plate, an -insulating terminal block on said plate having slots in one face connecting with contact recesses opening into an opposite face, contact and terminal assemblies mounted on said block in said recesses in combination with an electromagnetic switch unit comprising a switch supporting plate slidable over said base plate and attachable to and separable from said base plate, an insulating contact supporting block mounted on said switch plate, contact and terminal members mounted on said switch contact block with prong-like terminal portions extending therefrom and engageable through said slots with the contact portions of said contact and terminal assemblies upon sliding `of said switch unit toward said terminal block, movable contact means and electromagnetic actuating means therefor both supported from said switch plate, whereby said switch unit may be slid along said base plate to make a plug-in connection with said mounting block, and means to guide the motion of the switch unit toward the terminal block when said prong-like portions enter said slots, comprising guide slot and stud means on said base and switch supporting plates insulated from said contact and terminal members.

2. The combination of claim 1 wherein the stud means comprises a plurality of securing devices in said base plate fitting in slots in said switch supporting plate, said securing devices being turnable to aflx the switch unit yon said base plate in plugged-in position.

3'. The combination of claim 1 having L-shaped switch contact -and terminal members with one leg of each member extending beyond its supporting block and forming said prong-like terminal portions, the other leg having a contact surface thereon for engagement by a movable v contact.

thereon, movable contacts engageable with and separable from said fixed contacts, a movable carriage for operating said movable contacts, an armature pivotally mounted on said carriage, a solenoid coil and a field piece detachably mounted on said supporting plate, said coil, field piece and armature being swingable together about the pivotal armature mounting away from said supporting plate when said field piece is freed from said plate.

5. An electromagnetic switch as claimed in claim 4 in which the armature is T-shaped and its pivot passes thru the center of the head.

6. An electromagnetic switch comprising a supporting plate, an insulating block having fixed contacts mounted thereon, movable contacts engageable with and separable from said fixed contacts, a movable carriage for operating said movable contacts, an armature pivotally mounted on said carriage, a solenoid coil and a field piece detachably mounted on said supporting plate, said coil, iield piece and armature being swingable together about the pivotal armature mounting away from said supporting plate when said eld piece is freed from said plate without atecting said carriage and fixed and movable contact assemblies, and while said carriage and assemblies remain in assembled condition.

7. An electromagnetic switch comprising a supporting plate, an insulating block having fixed contacts mounted thereon, movable contacts engageable with and separable from said xed contacts, a movable carriage for operating said movable contacts, an armature pivotally mounted on said carriage, means on said plate extending on each side of said armature and having parallel guide slots, a pivot pin passing thru said armature and extending into and guided by said slots to guide the armature movement, a solenoid coil and a field piece detachably mounted on said supporting plate, said coil field piece and armature being swingable together about the pivotal armature mounting away from said supporting plate when said field piece is freed from said plate.

8. An electromagnetic switch comprising a supporting plate, an insulating block having fixed contacts mounted thereon, movable contacts engageable with and separable from said fixed contacts, a movable carriage for oping into and guided by said slots to guide the armature movement, a solenoid coil and a field piece detachably mounted on said supporting plate, said coil field piece and armature being swingable together about the pivotal armature mounting away from said supporting plate when said field piece is freed from said plate without affecting said carriage and fixed and movable contact assemblies and while said carriage and assemblies remain in assembled condition.

9. An electromagnetic switch comprising a supporting plate, an insulating block having fixed contacts mounted thereon, movable contacts engageable with and separable from said fixed contacts, a movable carriage for operating said movable contacts having means extending forwardly, an armature pivotally mounted on said forwardly extending means to -rnove the carriage, means on said plate extending on each side of said armature and parallel to said forwardly extending means and having parallel guide slots, a pivot pin passing thru said armature and extending into and guided by said slots to guide the armature movement, a solenoid coil and a iield piece detachably mounted on said supporting plate, said coil eld piece and armature being swingable together about the pivotal armature mounting away from said supporting plate when said field piece is freed from said plate.

References Cited in the tile of this patent UNITED STATES PATENTS 1,322,097 Dunham Nov. 18, 1919 2,010,677 OKeefe Aug. 6, 1935 2,087,895 Bierenfeld July 27, 1937 2,172,633 Wilms Sept. 12, 1939 2,239,031 Bierenfeld et al. Apr. 22, 1941 2,304,972 Van Valkenburg et al. Dec. 15, 1942 2,394,090 McFarland Feb. 5, 1946 2,449,221 Hammerly Sept. 14, 1948 

